Synthetic polymers, for instance, those based upon allyl resins such as diallyl glycol carbonate or polycarbonates, are used extensively for eyeglass lenses, other lenses in the optical industry, and such as sheet glazing material for windows or parts used in building construction, vehicles such as trains, cars, airplanes, ships, and the like. Such polymeric lenses and sheets are advantageous since they can be manufactured inexpensively by casting or injection molding, making it possible to obtain thereby complicated surface configurations directly without expensive grinding. While the diallyl glycol carbonates as a class of polymers are generally substantially resistant to abrasion and scratching as compared to polymethylmethacrylates, it is desirable to increase their abrasion resistance by applying thereto a hard transparent protective layer.